i found this interesting site concerning language related problems, particularly problems encountered when switching over between laguages. This site is apparently the idea of a group of very highly qualified and competent guys who work for :: Institute for Research in Cognitive Science at the University of Pennsylvania.
It has examples of some hilarious and not so hilarious translations and malapropisms.
The site can be found at ::
http://languagelog.ldc.upenn.edu/nll/
Take a look,
partha
The Professor shares his discoveries, so that you can share them with others.
2010-08-07
2010-08-03
Method of invariants
I read an excellent article on the "method of invariants", a less known but powerful tool for mathematical problem solving. The article, by Rajaram Bhat, appeared in the July 2010 issue of RESONANCE. This journal, RESONANCE, is another remarkable journal, and is published in India, by the Indian Academy of Sciences. You can browse this journal and back issues from their website ::
www.ias.ac.in/resonance/.
partha
www.ias.ac.in/resonance/.
partha
2010-08-02
The randomness of randomness
The randomness of randomness
GOD does not play dice .... Albert Einstein.
It all started with a rather innocent looking question on the Internet. Here is how it ran: Given a number (only one), we can answer certain questions about it e.g. is it a prime ? is it an even number ? etc. Now, given a number (only one) can we say if it is a random number ? Why not ?
I posted the above question on the net, and got some replies, all of which gave rise to more questions.
Some of the responders were statisticians in the traditional sense. And predictably, they took examples of their pet random process: tossing a coin, or casting a die. Yes, given no other information, such experiments may be considered to give random outcomes (will it be a head ? will be a tail ? will the die yield an even number ? will the next child be a boy ? ...). But, there is a catch somewhere deep within this premise. A physicist friend of mine argued that there could be no such thing as a random number generated by such devices (die, coin). After all, the outcome of a toss is bound by strict laws of physics. It is a different thing that we cannot measure exactly the various parameters influencing the outcome e.g. the force exerted by the thumb when tossing a coin, the velocity of air, temperature gradients, ballisttics etc. etc. All of these are important, to determine the exact trajectory of the coin, and hence the exact outcome of this experiment. If we could measure (and control) all these, there will be no such thing as a random toss. We can put forth such arguments for all such so-called random phenomena when they involve physical devices and objects.
We will stop tossing coins in the air, or throwing dice on the table, and look for some non-physical phenomenon, for generating random numbers. Let us look at the last digit of the first n (assume n=20 for this case) prime numbers [1]. Here is what we get:
2 3 5 7 1 3 7 9 3 9 1 7 1 3 7 3 9 1 7 1
Looks like a perfect chain of random numbers (perhaps generated
by a ten-faced die). Wrong again -- we can predict exactly the
21st digit which follows the last one above: 3 (the 21st prime
is 73) . Look at this from another viewpoint. Suppose we decide
to write these random numbers in a binary notation. And now, we
look at the last digit only (in this case we must call it a bit).
Here is what we will get:
0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 ....... ad infinitum.
Nothing could be more predictable than this series !
Now, let us look at the first n (n=20) primes themselves ( The first 1000 primes :: http://www.utm.edu/research/primes ):
2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71.... ??
If we know the magic potion which was used for generating the above numbers, then we can predict exactly the number which must follow (the 21st prime number in the series). If we ignore for a moment the monotonically increasing magnitudes, and if we hide the common phenomenon behind these numbers (the fact that they are all primes), we probably have a good candidate for random numbers. Suddenly, the same 21st number becomes random and unpredictable !
The conclusion is simple, there is no such thing as a true random number ! It is just whether we are or we are not able to formalise the underlying generating phenomenon that makes all the difference. Some people prefer to use a more explicit term: non-deterministic phenomenon , to refer to such processes.
Let us go back and look at the question which started all this. The answer is a big NO, because: .... we let the reader work out the arguments. (They rightly say so ...By just looking at the tracks, you can't say which way the train went.)
PS :: If you wish to comment on this, please send me a direct mail : drpartha AT gmail DOT com
* * * *
GOD does not play dice .... Albert Einstein.
It all started with a rather innocent looking question on the Internet. Here is how it ran: Given a number (only one), we can answer certain questions about it e.g. is it a prime ? is it an even number ? etc. Now, given a number (only one) can we say if it is a random number ? Why not ?
I posted the above question on the net, and got some replies, all of which gave rise to more questions.
Some of the responders were statisticians in the traditional sense. And predictably, they took examples of their pet random process: tossing a coin, or casting a die. Yes, given no other information, such experiments may be considered to give random outcomes (will it be a head ? will be a tail ? will the die yield an even number ? will the next child be a boy ? ...). But, there is a catch somewhere deep within this premise. A physicist friend of mine argued that there could be no such thing as a random number generated by such devices (die, coin). After all, the outcome of a toss is bound by strict laws of physics. It is a different thing that we cannot measure exactly the various parameters influencing the outcome e.g. the force exerted by the thumb when tossing a coin, the velocity of air, temperature gradients, ballisttics etc. etc. All of these are important, to determine the exact trajectory of the coin, and hence the exact outcome of this experiment. If we could measure (and control) all these, there will be no such thing as a random toss. We can put forth such arguments for all such so-called random phenomena when they involve physical devices and objects.
We will stop tossing coins in the air, or throwing dice on the table, and look for some non-physical phenomenon, for generating random numbers. Let us look at the last digit of the first n (assume n=20 for this case) prime numbers [1]. Here is what we get:
2 3 5 7 1 3 7 9 3 9 1 7 1 3 7 3 9 1 7 1
Looks like a perfect chain of random numbers (perhaps generated
by a ten-faced die). Wrong again -- we can predict exactly the
21st digit which follows the last one above: 3 (the 21st prime
is 73) . Look at this from another viewpoint. Suppose we decide
to write these random numbers in a binary notation. And now, we
look at the last digit only (in this case we must call it a bit).
Here is what we will get:
0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 ....... ad infinitum.
Nothing could be more predictable than this series !
Now, let us look at the first n (n=20) primes themselves ( The first 1000 primes :: http://www.utm.edu/research/primes ):
2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71.... ??
If we know the magic potion which was used for generating the above numbers, then we can predict exactly the number which must follow (the 21st prime number in the series). If we ignore for a moment the monotonically increasing magnitudes, and if we hide the common phenomenon behind these numbers (the fact that they are all primes), we probably have a good candidate for random numbers. Suddenly, the same 21st number becomes random and unpredictable !
The conclusion is simple, there is no such thing as a true random number ! It is just whether we are or we are not able to formalise the underlying generating phenomenon that makes all the difference. Some people prefer to use a more explicit term: non-deterministic phenomenon , to refer to such processes.
Let us go back and look at the question which started all this. The answer is a big NO, because: .... we let the reader work out the arguments. (They rightly say so ...By just looking at the tracks, you can't say which way the train went.)
PS :: If you wish to comment on this, please send me a direct mail : drpartha AT gmail DOT com
* * * *
2010-07-30
ACM Honours, for a lady genius
Quoted from IITD LUG mailing list ::
QUOTE
Madam Radia Perlman will be honored for contributions to Computer
Networking as she wins ACM SIGCOMM Award for Pioneering Advances in
Internet Communication.
Radia Perlman
She worked mostly on the spanning tree protocols, convergence and
stability properties of link state routing. Her book
'Interconnections' has been helpful for many generations of budding
Internetworking professionals.
UNQUOTE
QUOTE
Madam Radia Perlman will be honored for contributions to Computer
Networking as she wins ACM SIGCOMM Award for Pioneering Advances in
Internet Communication.
Radia Perlman
She worked mostly on the spanning tree protocols, convergence and
stability properties of link state routing. Her book
'Interconnections' has been helpful for many generations of budding
Internetworking professionals.
UNQUOTE
2010-07-22
How to comment on my blogs .....
It is always a pleasure to notice the number of people who care to read my blogs, and also leave comments. Unfortunately, I am not able to decide on accepting or rejecting your comments, unless I know who you are. The notice for moderation I get from blogspot, does not give me your mail ID, so I cant actually check back with you.
Please remember to send me a separate mail with your comments and your mail ID too. Also identify yourself, tell me something about yourself, wher you are located, and what do you do in real life when you are not blogging. You see, I give all these details and much more in my websites which you can access from my blog pages.
Since I would also like to send a personal thanks message, so I must know your mail ID.
Many thanks, and keep the comments flowing (along with your details).
partha
drpartha AT gmail DOT com
Please remember to send me a separate mail with your comments and your mail ID too. Also identify yourself, tell me something about yourself, wher you are located, and what do you do in real life when you are not blogging. You see, I give all these details and much more in my websites which you can access from my blog pages.
Since I would also like to send a personal thanks message, so I must know your mail ID.
Many thanks, and keep the comments flowing (along with your details).
partha
drpartha AT gmail DOT com
koha in Kerala
The Government of Kerala, a tiny well-developed state lying in the south-west part of India, has recently made a decision in principle to make Koha as its official software for computerization of libraries under Government control. It is going ahead with further steps to implement the project by The Directorate of Technical Education in association with the Community Development Centre, Government Polytechnic, Kalamassery.
Details are here :: http://kohaindia.org/news_details.php?newsID=6
(Qouted from the koha-india website mentioned above)
Kerala has always been a progressive state, and has been promoting FOSS, in various ways.
partha
Details are here :: http://kohaindia.org/news_details.php?newsID=6
(Qouted from the koha-india website mentioned above)
Kerala has always been a progressive state, and has been promoting FOSS, in various ways.
partha
koha -- library management FOSS
The heart of any good institution is its library. Many institutions take pride in making the library their showcase. Many institutions, like the one I was in till recently, have a shabby and outright repulsive hole which they call their library. If you belong to an institution which has a library and is willing to make it a place worth visiting, you will need a good library management system. There is help from the FOSS community :: koha
Get details about koha from here :: http://koha.org/
In India there is a koha community. Get details here :: http://kohaindia.org/
partha
Get details about koha from here :: http://koha.org/
In India there is a koha community. Get details here :: http://kohaindia.org/
partha
The LFS book...free
If you really want to try, you can download and read a whole book
on Linux from Scratch, written by Beekman, the author of LFS,
from here ::
http://oss.sgi.com/LDP/LDP/lfs/lfs.pdf
The lfs book is 322 pages long. The pdf file is 940973
bytes. In fact, I would recommend that book to teachers (like me)
who teach OS
Ask me for a copy , if you are not able to download from the
above site. Of course students from Wargal, please stay away. this book is much beyond your level.
Best of luck, and keep trying,
partha
on Linux from Scratch, written by Beekman, the author of LFS,
from here ::
http://oss.sgi.com/LDP/LDP/lfs/lfs.pdf
The lfs book is 322 pages long. The pdf file is 940973
bytes. In fact, I would recommend that book to teachers (like me)
who teach OS
Ask me for a copy , if you are not able to download from the
above site. Of course students from Wargal, please stay away. this book is much beyond your level.
Best of luck, and keep trying,
partha
One more student project....
This is for the adventurous, and above average student (or a group of such students). It is certainly not for the kind of students I have seen recently at Wargal (Hyderabad). You can build your on OS from the basics. Learn how to fit in all the pieces of a huge jigsaw puzzle. Have fun. Become a geek, and an OS guru. "Linux from scratch" is for people who fit the above profile.
Get details here ::;
http://www.linuxfromscratch.org/
Or ask me if you need details.
partha
PS: Students I have seen recently at Wargal (Hyderabad), please stay away.
Get details here ::;
http://www.linuxfromscratch.org/
Or ask me if you need details.
partha
PS: Students I have seen recently at Wargal (Hyderabad), please stay away.
2010-07-21
Astrology, myth, or reality ?
Just received the book -- Astrology -- believe it or not ? (S Balchandra Rao, Pub. : Navakarnataka Publishers). The author, a reputed mathematician, examines astrology in an impartial and rational sense. His study is rigorous, based on clear mathematical concepts, and demonstrates how mathematical concepts are distorted, to form a pseudo science called astrology. People confuse the fuzzy pseudo-science of astrology with the precise science of astronomy (a branch of mathematics), and intersperse their arguments using names of great sages like Varahmihira or Parshara or Jaimini. By juxtaposing these names with their own terminology, they create a certain euphoria which has still not been proven conlusively. This book is just the kind one has to read, to know the true worth (or otherwise) of astrology.
It is a pity I have no way to contact the author, to congratulate him and thank him.
I thank my friend Natarajan, who could procure this book for me.
partha
PS : I located this book, based on a review I read in RESONANCE (a brilliant journal produced by the Indian Academy of Science)
It is a pity I have no way to contact the author, to congratulate him and thank him.
I thank my friend Natarajan, who could procure this book for me.
partha
PS : I located this book, based on a review I read in RESONANCE (a brilliant journal produced by the Indian Academy of Science)
Subscribe to:
Posts (Atom)